Smartphone users the world over have become fans of the game. Angry Birds is easy to understand and addictive as well. Using the touchscreen on a cell phone or tablet PC, users aim a slingshot at pigs in increasingly complicated fortifications. Angry Birds was the most successful game app of 2010 and 2011, earning Rovio millions. The company also makes money by merchandising all sorts of upgrades and related products. In late March, the makers are taking Angry Birds to a new level: Angry Birds Space. The hype is already well underway.